Monthly Archives: June 2011

At the recent IEEE International Conference on Distributed Computing Systems (ICDCS) in Minneapolis, Dong Xuan (associate professor of computer science and engineering at Ohio State University) introduced a smartphone App called eShadow that uses nearby wireless networks and smartphones’ wireless communications to tell users that a friend who also uses the software is nearby, and even gives directions to that friend’s location. At first blush this seems a natural extension of social trends like foursquare and Yelp, which utilize the geolocation of an individual to interact with others online. Social networking is about interacting, so meeting in the “real world” would seem an obvious next step.

Actually, before I thought about that, I had to force myself to get past the similarity of Xuan’s name to Don Juan, and how a character like Juan could really benefit from an App that helped him pick up women. Is it just me, or does it seem that quite often the name given of a scientist in a study being covered in the news contains an irony fitting to that particular study? If it’s a study on mating habits of Chimps, the lead scientist’s name will be Ben Dover or something like that. I haven’t done a formal study on this, but one should be done. The coincidence seems unlikely. Anyway, back to the actual topic…

The researchers working on eShadow stated that their biggest challenge had to do with efficient use of the wireless signals. They had to develop algorithms that let the phones send and receive signals quickly to keep from clogging up the network. When tested on the Ohio State campus, eShadow took an average of 25 seconds to connect two users who were 20 to 50 yards apart, and 35 seconds for seven users.

Apparently Xuan suggested a military application for the software, allowing soldiers to locate each other on the battlefield. I’m a bit skeptical about the usefulness there, as it would also allow the enemy to easily lead soldiers into traps with a bit of hacking.

Despite my normal skeptical eye through which I peek at most new products (software included) I think that Xuan and his team are on to something with eShadow. As someone who’s developed websites professional for a bunch of years now, I’ve done a lot of following of online technology as it develops, and a lot of speculation on where it’s likely to lead to. What I’ve seen is that the success of a device/application is almost always directly connected to the ease of the interface. It doesn’t end up mattering if there’s a point to doing something – as long as you can make it easy to do, people will do it. (Twitter comes to mind.) A good example is the success of devices like the iPhone with touchscreens, over the old BlackBerry and Newton. The iPhone improved on the miniscule buttons that hamfisted guys like me couldn’t manage. But many of the tasks are the same, while admittedly a bit more developed.

What eShadow is hinting at is the world where we can automate a good deal of our societal interactions. We’ve seen this in science fiction for some time. There’s already been a progression from desktop to laptop to handheld, and the next logical steps are visual and then actual brain interfaces. (And people are definitely already working on that.)

My hope is that by the time software like eShadow is ubiquitous, that someone takes into consideration the role that chance plays in social interactions. Software can easily match up likes and dislikes, sorting us like a bunch of library index cards, but with us humans it’s not always the best way to find others that we hit it off with. It could be that your next best friend or partner for life is someone who has opposite viewpoints and tastes, or even somewhere in the spectrum between same and opposite. Once we have algorithms that can make sense of us on that level, things will really begin to change in interesting ways.

The particular critter featured in the study was the tide pool copepod Tigriopus californicus, a tiny shrimp-like animal found between Alask and Baja California, and the primary focus of the study was whether they could evolve a tolerance to increased temperature. Morgan Kelly, a UC Davis grad student collected copepods from eight different locations and grew them in the lab for 10 generations, under increasing heat to see if natural selection would produce more heat-tolerant progeny. They apparently failed to do so.

UC Davis Professor Rick Grosberg concludes that this study implies widespread species don’t have enough genetic capacity to work with in order to adapt to climate change, and also blames human interference with disrupting and fragmenting habitats to the point of damaging the ability for many species to survive. Grosberg believes that many species are already at their “environmental limits” and that natural selection won’t necessarily save them.

Now, I’m not an evolutionary biologist, and I don’t even play one on TV. But I found myself with a lot of questions while reading the article. Whatever your political views on global warming, it’s fairly obvious that the Earth is constantly in a state of climate change in that the climate is, well, always changing. There are long and short cycles, but there is a form of chaos inherent to the process. This is why forecasting the weather is still so difficult. Lets also assume for the moment that we are on an upward trend in global temperature. I don’t want to get into the debate on whether it’s caused by man, or is part of a natural trend. What I find myself wondering is how this study applies to evolution as a whole.

Many more studies would have to be done to show any sort of evidence of a multi-species trend in a lack of ability to adapt to conditions, but my understanding of evolution and natural selection is that climate is often the major driving force. It’s also my understanding that it’s not about all the existing species finding some way to “upgrade” to the right hardware to get them through another year. Individual living things die, species die, and as a whole, life evolves to fit the new environment because what doesn’t fit is no longer around.

Climate change isn’t new. Around 2.4 billion years ago, Earth’s atmosphere had practically no oxygen. Life as we know it would have found it a toxic environment. Evidence indicates that back then, the planet was home to scattered smatterings of shallow-water, photosynthetic microbes that produced oxygen as waste. After enough of this waste built up, toxic to life common to that time, adaptations allowed new branches of life to flourish which could make use of this new environment. (See “Learning to Live With Oxygen on Early Earth”.) The rate of the change in environment will obviously have an effect on the particulars of which species change and which die, but it doesn’t easily change the process itself.

So while the study may do a good job at proving that Tigriopus californicus may not be around for the long haul, I fail to see how it indicates anything like what the main thrust of the commentary seemed to be. I find myself wondering if it’s not a case of confirmation bias involving political views.

(NOTE: this is intended to be an opinion piece not a scientific claim – whether you agree or disagree I invite you to comment and include your own thoughts, especially if you have additional science/evidence to bring with you.)

If you want to comment or ask us a question, you can email us at podcast@miskeptics.org or fill our our Contact Form. Also you can now call us on the phone! Give us a drunk dial on our Drunken Skeptic line, 734-719-0274 (U.S. number) and leave a message. If we like it, think it was a good comment (or the check clears) we may play it on the podcast!

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The conditions are set for a bumper crop of mosquitoes this summer in Michigan. Mosquito populations come in waves, and as the spring mosquitoes are dying off, the summer mosquitoes are set to emerge followed by another peak in the population early July. Summer mosquitoes thrive in warm weather and breed in stagnant waters. Following a rainy month of May that left water tables high, it could be perfect conditions for an especially large population of those nasty pests that leave us all itching for relief.

Mosquitoes have a great impact on our quality of life as we try to enjoy the great outdoors, but they also harbor disease organisms and pass them on to humans and other animals. Examples of this are Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV), mosquito-borne viruses that can be found in Michigan. The best way to reduce the risk of infection by mosquito-transmitted diseases is to reduce exposure. The Michigan Mosquito Control Association has a few recommendations to reduce exposure to the hungry mosquitoes: Wear long sleeved shirts and long pants, try not to go outdoors during hours of peak mosquito activity (dusk and dawn), keep all window and door screens in good repair, and wear mosquito repellents containing DEET, picaridin, or oil of lemon eucalyptus, making sure to read repellent labels before use.

The most common and effective chemical used in commercial repellents is N, N-diethyl-3-methylbenzamide (DEET). DEET has over a 50 year history of use, first becoming commercially available in 1957. Despite the numerous lay press reports questioning the safety of DEET, this repellent has been subjected to more scientific and toxicologic scrutiny than any other insect repellent. DEET has a remarkable safety profile spanning the last half century with over 8 billion human applications. Still, there have been significant efforts in academia, government and private sector to identify new insect repellents. This has largely been driven by reports of DEET toxicity, minimal efficacy towards certain subspecies of insects, high incidences of insect-borne diseases, decreasing consumer acceptance and the potential for insects to develop resistances.

In the search for alternatives, thousand of plants have been screened as potential insect repellents from botanical sources. Most plant-based insect repellents on the market contain essential oils from one or more of the following plants: geranium, citronella, cedar, eucalyptus, peppermint, lemongrass, and soybean. Products made from oils-of-eucalyptus perform the best out of these examples.

Catnip is another example historically used as an insect repellent and as a folk lore remedy. Although not native to North America, catnip now grows throughout Michigan and is generally considered a weed. Nepeta cataria (also known as catnip, catswort, or catmint) is a plant in the Lamiaceae family. The common names can also be used to refer to the Nepeta genus as a whole. The main chemicals in oils of catnip were identified to be nepetalactones, consisting primarily of two isoforms. Here I review some of the recent studies on catnip for its ability to repel mosquitoes.

Field tests were conducted using a hydrogenated form of catnip oil in Florida and Maine. First, the essential oil of catnip was catalytically hydrogenated to yield dihydronepetalactones (DHN). Strictly speaking, hydrogenated catnip oil (HCO) is not something the average person can make without a palladium catalyst, hydrogen gas and a pressure vessel. DHN was previously detected in the defensive secretions of certain insects and it had been reported that DHN had the ability to repel ants. HCO was formulated into a lotion or alcohol-based spray. All HCO formulas exhibited some degree of extended protection with the 15% by weight HCO lotion providing complete protection during the eight hour tests. The authors suggest that formulations of HCO can be effective alternative to existing repellents such as DEET.

In Australia, a commercial product containing 5% catnip essential oil was tested as repellent against four different species of mosquitoes. Significant variation was observed for protection afforded against different mosquito species ranging from no protect to four hours on average. In contrast, a 7% DEET spray provided complete protection over a six hour period. Overall, the authors concluded that catnip does provide limited protection against some mosquito species in Australia, and may be more effective than other products containing natural plant extracts, but it was not as effective as DEET.

A study from China compared catnip essential oil along with other plant essential oils and DEET. Catnip essential oil (composed of 36%, 45%, 18% isomer 1, isomer 2, and caryophyllene) provided the best protection against mosquitoes and the only oil to provide complete protection for over six hours. When testing the major ingredients of catnip oil, their tests showed that a blend containing the nepetalactone isomers at a 3:1 ratio has the highest and longest repellent activity.

The most recent study published in 2011 on the use of catnip essential oils was performed on Afro-topical mosquitoes originally cultivated from Tanzania. They compared two different batches of catnip and found that the isomeric composition of nepatalactone varied considerable (batch A: 92% isomer 1 and 8% caryophyllene, and batch B: 17% isomer 1, 70% isomer 2, and 13% caryophyllene). Upon testing, batch A was not as effective at repelling mosquitoes as compared to batch B. Purified isomers provided inferior protection to either batches of essential oils. Testing of binary mixtures confirmed the synergistic effect between the two isomers. Lower activity was seen with purified isomers and, surprisingly, with equivalent or near equivalent binary mixtures. Highest activity was afforded when the isomers were mixed in 3:1 ratios. Furthermore, a ratio mixture equivalent to batch B did not perform as well compared to either batch of essential oils. A three component blend containing caryophyllene at the levels found in batch B had the same activity as the essential oil.

Typical of plant extracts, the concentration of active ingredients various from batch to batch and the variation is dependent upon things like supply location, seasonal variations, age of the plant, and extraction procedure. Indeed, the ratio of isomers within a catnip plant was shown to vary weekly and the effectiveness of the essential oils to repel insects varied greatly.

Overall, the research on catnip essential oil has proven it to be an effective repellent of mosquitoes. Some variation on the species of mosquitoes repelled and the duration of effectiveness was found. The data suggests that catnip can be used as an effective insect repellent when used as an unfractionated essential oil due to the presence of both nepetalactone isomers and other components such as caryophyllene. However, for practical use of these plant essential oils, further studies on their safety to human health are necessary.

Many of the articles cited are behind paywalls. Copies of specific articles will be provided upon request.

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At the recent D9 tech conference in Rancho Palos Verdes, California, Meredith Perry and Nora Dweck demonstrated their ability to send electrical power ultrasonically (beyond the range of human ears) with their prototype device. In this case we’re talking about a “proof of concept” version sending about a quarter of a watt over a three foot distance. The idea is to provide a device that would be like wifi but for electrical power instead of Internet access.

They company they have created to work on their idea is called uBeam. (Upon first glance at the company name, two mutated memes instantly began competing in my brain. The “iBeam, uBeam, we allBeam for iBeam” line and of course Apple-ish little letter followed by a capitalized word. Whether those are actually memes, and whether memes actually exist, I’ll save for a future post.) Anyway, I was attracted to this story because a few years ago I started wondering why we couldn’t use the Earth’s magnetic field as a kind of carrier wave to provide truly comprehensive Internet access everywhere on the planet. Not the same thing, but it reminded me of it nonetheless.

Despite it’s geek appeal, there seem to be some fundamental problems with the technology. One easy one to notice is that when her hand blocks the signal the power drops off in a big way. Sort of like the problem that clouds pose for ground based solar power collectors. Altering the distance between emitter and receiver even a few inches also appears to have a large noticeable effect, which makes sense since a sound wave rapidly loses energy as it travels from it’s source. (This is why it’s hard to hear someone waaaaaay over there as opposed to right here.)

I found it interesting to learn after some Googling that wireless power isn’t all too new a dream. Nikola Tesla tried to make this happen over a hundred years ago.

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Come on out for an evening of like minded folks getting together to discuss and to laugh.

This is most of the people that attended our first Get together. I could not get an angle that would fit everyone.

Come and join us for lively discussion, drinks, dinner and debate! This is a good event for Skeptics of Michigan to come together and discuss local, national, worldwide items affecting skeptics. All are welcome to listen and participate.

This month is our social meeting so be prepared to talk, discuss and most of all, laugh!

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The Drunken Skeptics are back! The long hiatus is finally over and we are once again making shows that annoy the pious and the sober.

What unicorn?

In this episode, we talk with Tom and Kate Borninski of Camp Quest Michigan. A secular summer camp for kids of freethinking families.

Camp Quest is the first residential summer camp in the history of the United States for the children of Atheists, Freethinkers, Secular Humanists, Humanists, Brights, or whatever other terms might be applied to those who hold to a naturalistic, not supernatural world view.

If you want to comment or ask us a question, you can email us at podcast@miskeptics.org or fill our our Contact Form. Also you can now call us on the phone! Give us a drunk dial on our Drunken Skeptic line, 734-719-0274 (U.S. number) and leave a message. If we like it, think it was a good comment (or the check clears) we may play it on the podcast!